Codes

Unlock Midday Constellation (Noon Star) Booster

At the shop screen where you select the boosters, Enter The Following Code:

Effect

Code

Midday Constellation Booster

Up, Up, Down, Down, Left, Right, Left, Right, X, O.

Passwords

Card Passwords

Go to the Lab, when it finally appears, and choose the password machine. Put in the following codes- note these cards will appear in the rental shop and you will be charged a fee that will come out of the duel points you win (I have more, but, I was unable to put them all on the form that Gamefaqs has provided):